std::regex_constants::syntax_option_type

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Defined in header <regex>
enum syntax_option_type {     icase = /*unspecified*/,     nosubs = /*unspecified*/,     optimize = /*unspecified*/,     collate = /*unspecified*/,     ECMAScript = /*unspecified*/,     basic = /*unspecified*/,     extended = /*unspecified*/,     awk = /*unspecified*/,     grep = /*unspecified*/,     egrep = /*unspecified*/, };     constexpr syntax_option_type operator~(syntax_option_type f); constexpr syntax_option_type operator&(syntax_option_type lhs, syntax_option_type rhs); constexpr syntax_option_type operator|(syntax_option_type lhs, syntax_option_type rhs);

The syntax_option_type is a type that contains options that govern how regular expressions behave.

[edit] Constants

^ Value ^ Effect(s) if set ^ |icase|character matching should be performed without regard to case| |nosubs|when performing matches, no sub-expression matches should be stored in the supplied regex/match_results structure| |optimize|instructs the regular expression engine to make matching faster, with the potential cost of making construction slower. For example, this might mean converting a non-deterministic FSA to a deterministic FSA.| |collate|character ranges of the form "[a-b]" will be locale sensitive| |ECMAScript|use a modified version of the ECMAScript regular expression grammar (ECMA-262)| |basic|use a basic POSIX regular expression grammar| |extended|use an extended POSIX regular expression grammar| |awk|use the regular expression grammar used by the awk utility in POSIX| |grep|use the regular expression grammar used by the grep utility in POSIX| |egrep|use the regular expression grammar used by the grep utility, with the -E option, in POSIX|

[edit] Operators

Bitwise operators ~, &, and | are also defined for syntax_option_type.